Calcium phosphates, such as hydroxyapatite, β-tricalcium phosphate (β-TCP), and octacalcium phosphate (OCP), are used as bone regeneration materials (e.g., PTL 1 to PTL 5). Moreover, PTL 5 proposes incorporating OCP into a porous body made of collagen so as to impart shape-retaining properties to the OCP. Furthermore, NPL 1 reports that a collagen porous body containing OCP has a more excellent bone-regeneration effect than OCP alone.
NPL 2 reports that local bone formation was significantly promoted by subcutaneous administration of parathyroid hormone (PTH). NPL 2 also reports that bone formation by β-TCP is limited, and that the bone-forming effect by PTH is inhibited by the combined use of PTH and β-TCP.